Lamp socket



1950 HANS-ERIK JOHANSSON 2,531,686

LAMP SOCKET Filed Dec. 8, 1947 Patented Nov. 28, 1950 UNITED STATES PATENT OFFICE LAMP SOCKET Hans-Erik Johansson, Lessebo, Sweden Application December 8, 1947, Serial N 0. 790,317

In Sweden December 11, 1946 The present invention relates to lamp sockets and has for its principal object to provide a combinable lamp socket affording a considerable simplification of the manufacture of the most commonly used types of lamp sockets, viz. normal lamp sockets, full-thread lamp sockets and wall lamp sockets.

According to a broad aspect of the invention the object mentioned is attained by providing in combination a lamp socket capable of being employed separately as a normal lamp socket, and an outer socket for said lamp socket and having provision for one or more special functions, said lamp socket and said outer socket being provided with complementary interengagement means for detachably securing the same together so as to obtain a special lamp socket.

By this arrangement it will no longer be necessary to manufacture and store separate normal sockets, full-thread sockets and wall sockets (by a full-thread socket is in this specification and claim ,meant a socket provided along a major portion, at least, of its length with a continuous external thread). Thus it will only be necessary to manufacture one single type of lamp socket which is capable of being used separately as a normal lamp socket, and, in addition, a few different types of outer sockets adapted to receive said normal socket when a special lamp socket is desired. Thus, if a full-thread lamp socket for floor or like lamps required to carry a shade or the like is desired, the normal lamp socket should be combined with an externally threaded outer socket. If a wall lamp socket is desired the normal lamp socket should be combined with an outer socket formed with a base adapted to be secured to a wall, said outer socket being preferably externally threaded for mounting a shade or the like thereon. In order to provide for these different kinds of lamp sockets, accordingly, it will be sufilcient to manufacture normal lamp sockets, wall bases having outer sockets extending at right angles thereto, wall bases having outer sockets extending in an inclined direction therefrom, and externally fullthreaded straight sockets.

Other objects and advantages of my invention will appear in the course of the following description, read in connection with the accompanying drawing, of three representative embodiments of my combinable lamp socket, though it is to be understood that changes may be made without departing from the spirit of the invention as defined by and within the scope of the claim hereunto appended.

1 Claim. (01. 173--362l In the drawing:

Fig. 1 is a longitudinal section through a fullthread lamp socket, combined according to'the invention, and I Figs. 2 and 3, respectively, show two different forms of combined wall lamp sockets, the base and outer socket being shown in axial section and the normal lamp socket inserted therein being shown in side View.

Referring to Fig. 1 the combined full-thread lamp socket comprises a normal lamp socket including a bottom or base member I, an outer or holder member 2 detachably connected to said bottom member I, and contact elements, an insulating insert and connecting elements, all in a well-known manner, as is shown in the figure. According to the invention the outer rim of the bottom member I is provided with an external thread II which is preferably left handed. The outer edge of the holder member 2 is formed with a continuous annular shoulder I3. If desired, this shoulder may, however, be replaced by one or more circumferentially spaced shoulder or stops. Accordingly, the construction just described is in effect simply a conventional normal lamp socket provided with an external left hand thread and a circumferential shoulder.

According to Fig. 1, however, the normal lamp socket described has been converted into a fullthread lamp socket by having mounted thereon an outer socket 3 provided with an external fullthread. The outer socket 3 is provided adjacent one end thereof with an internal left hand thread I2 for engagement with the left hand thread II of said normal socket I, 2. By screwing the outer socket 3 onto said normal socketthe leading edge of said outer socket is eventually tightened in abutment with said shoulder I3 on the member 2 of the normal socket. The external thread of said outer socket is preferably right handed in order to receive a right hand threaded shade holder ring 4 and any retaining rings or the like therefor. By forming the outer socket with oppositely handed external and internal threads any disengagement of one thread is prevented as the other is being operated.

Figs. 2 and 3 of the drawing show the lamp socket according to the invention so combined as to obtain wall sockets of the two main types, viz. wall sockets extending at right angles to the base (Fig. 2) and wall sockets extending in an inclined direction from the base (Fig. 3). In this instance, the separate outer socket I5 and I8, respectively, for the normal socket I, 2 is formed integrally with a wall base 20 provided with screw holes I! for mounting the same onto the wall by means of screws (not shown). After screwing the normal socket into the outer socket I5, I8, respectively, it may be secured in place by means of a stop screw [6. As is shown in Fig. 3, the wall base may be provided with a switch I9. As before, the outer socket is preferably provided with an external right hand thread for mounting a shade or the like.

It will be observed that the outer socket 3 of Fig. 1 may, in addition, be utilized as a tensioning element between a wall or ceiling and said normal socket i, 2, if the outer socket is screwed onto said socket in the direction opposite to that shown, whereby a very rigid mounting is ob tained.

What I claim and desire to secure by Letters Patent is:

A lamp socket device comprising in combination a complete standard lamp socket capable of being independently used, said socket Shavingqan' external screw thread adjacent one end thereof, an outer socket, said outer socket having an internal screw thread portion adjacent one end thereof engaging said external screw thread on said standard socket, an upstanding shoulder formed on said standard socket externally thereof at theend of said socket remote REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 960,807 Bundy June 7, 1910 1,015,963 Kleber Jan. 30, 1912 1,309,630 Hulse July 15, 1919 1,745,;691 Guth Feb. 4, 1830 1,988,321 Kollath Jan. 15, 1935 FOREIGN PATENTS Number I Country 7 Date 139,557 England Mar. 11, 1920 321,131 England Oct. 31, 1929 

